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View Full Version : Who pushes the thrust levers B737 and who steers the rudders?


Tee Emm
23rd Nov 2006, 22:24
Assuming manual throttle take off. My understanding from FCTM and Boeing FCOM is that for take off, the PF (whether he is captain or first officer doing the take off is immaterial) opens the thrust levers to ensure stabilization at 40% N1 Classic or 1.4 EPR on the 737-200 - then he also advances power to take off thrust, at which point the PM adjusts power only when it is already set at take off thrust.

Some operators however share the throttle duties and the PF opens up to stabilised thrust then hands the throttles over to the PNF who pushes them to take off thrust. In other words it differs from Boeing in that the throttle handling is split between the two pilots.

Boeing have no published procedure that requires split pilot duties in this regard. Who ever is handling pilot for take off is entirely responsible for his own throttle opening to take off thrust where the PM then is required to make any minor adjustments before 60 knots.

It seems to me that the danger of one chappie opening the throttles while the other chappie steers the aircraft on take off, is that if its a slippery runway and one engine spools slower than the other there will be hasty grabbing of throttles by the steering pilot who will feel the yaw.

Seems a straightforward Boeing recommended procedure from years of experience at selling aeroplanes is thrown out of the window so that both pilots get into the act - one shoving open throttles while one steers the centre line.
A bit superfluous - no?:=

Rainboe
24th Nov 2006, 07:17
Even the 737-200 should have autothrottle taking over final setting. As long as you are through high idle, then engine thrust response should be pretty even. As for final power setting manually, the PF cannot do it- his attention should be stay between the runway edges. This is where the PNF comes in. Otherwise, far better to let autothrottle do it.

BOAC
24th Nov 2006, 07:41
As Rainboe says, there should be little or no difference in accel from 40% min RPM, and what there is should not require throttle intervention by PF. If it is that bad:-

a) the a/c should have been snagged earlier OR
b) you should stop?

Im my experience, the way people do it is for PF to push the levers forward to where he/she reckons the correct position is and say 'Set take-off thrust' at which point PNF brings the engines back from the reheat range(:) ) and sets calculated TOGA.

A37575
24th Nov 2006, 14:06
To take it to the ridiculous stage I observed a SE Asian 737 crew in action in the simulator where the captain opened up the throttles to stabilisation 40% N1 then roared away down the runway at 40% N1 waiting for the comotose first officer to call "Stable, captain."

Unfortunately the first officer forgot to call "stable" mainly because he was momentarily unable to think up the right word. English was second language, you see.

Passing the 1000 ft runway markers at 45knots plus and accelerating with rpm still 40% and certainly stable, the captain finally got impatient and snapped at the hapless first officer of a mere 300 hours experience, and said "Hurry up - you haven´t called "Stable" yet. "Oops" said the first officer. "Sorry about that mein Kapitan - STABLE!" Ground speed was showing 65 knots and a lot of runway behind.

Boeing of course do not require a "stable" call - only that the parameter be observed and in any case no more than a two second hesitation at 40% N1. And the debacle described above only serves to prove that superfluous "support" calls mandated by company procedures can be very much counter-productive. :O

And that is where the simulator instructor froze the simulator and said WITHIGO "What-in-the-hell-is-going-on!"

mangatete
7th Dec 2006, 02:19
Seems the replies drifted off the question, submitter was inquiring about a manual thrust take off, that is the auto throttle not working or in use. Quite rightly, the supplementary procedures and the FCTM do not provide guidance for this event, however the DDPG (MEL) does allow operations with the auto throttle U/S... The FCOM does require the take-off thrust to be set by 60kts. PF should still advance for the 40% stabilization and then advance to approximate take-off thrust and call "Set Thrust". PM should then set thrust to -0% +1% target N1.
Cheers